import java.util.*;
import static net.mindview.util.Print.*;

class Tank {
    int level;
    void change(int a){
    a = 1;
    }
}

public class Assignment {
    public static void main(String[] args) {
        Tank t1 = new Tank();   
        Tank t2 = new Tank();
        t1.level = 9;
        t2.level = 47;
        
        print("t1:" + t1.level + "\nt2:" + t2.level);
        t1 = t2;

        t1.change(t1.level);
        print(t1.level);
    }
}   //不知道为啥单行注释总是报错，多行注释就没事